An Energy Efficient Semi-static Power Control and Link Adaptation Scheme in UMTS HSDPA

High speed downlink packet access (HSDPA) has been successfully applied in commercial systems and improves user experience significantly. However, it incurs substantial energy consumption. In this paper, we address this issue by proposing a novel energy efficient semi-static power control and link adaptation scheme in HSDPA. Through estimating the EE under different modulation and coding schemes (MCSs) and corresponding transmit power, the proposed scheme can determine the most energy efficient MCS level and transmit power at the Node B. And then the Node B configure the optimal MCS level and transmit power. In order to decrease the signaling overhead caused by the configuration, a dual trigger mechanism is employed. After that, we extend the proposed scheme to the multiple input multiple output (MIMO) scenarios. Simulation results confirm the significant EE improvement of our proposed scheme. Finally, we give a discussion on the potential EE gain and challenge of the energy efficient mode switching between single input multiple output (SIMO) and MIMO configuration in HSDPA.Comment: 9 pages, 11 figures, accepted in EURASIP Journal on Wireless Communications and Networking, special issue on Green Radi

Final report on the evaluation of RRM/CRRM algorithms

Deliverable public del projecte EVERESTThis deliverable provides a definition and a complete evaluation of the RRM/CRRM algorithms selected in D11 and D15, and evolved and refined on an iterative process. The evaluation will be carried out by means of simulations using the simulators provided at D07, and D14.Preprin

Performance evaluation of VoIP and web services in HSDPA

During the last years, the mobile communications market in the western developed countries has reached a standstill, with a market penetration higher than 100% in most countries such as, Spain 115%, United Kingdom 120% and Italy with more than 150%. So the network operators have focused their strategy in moving into a new market still developing, the data, that could help the operators to increase their saturated income. The solution mostly adopted by the operators is to offer the mobile broadband offering flat rate schemes to the customers for a monthly fee. The mobile broadband appeals to wide range of users, such as corporate users and especially to students which give them the liberty to access internet across different locations such as university, cafe or shared accommodation. That creates a set of challenges to the operators having to improve their network in order to cope with this huge new demand for high-speed data, to successfully satisfy these requirements, Third Generation networks must support high user data rates, especially on the downlink direction of the communication path due to its heavier load. For these reason, the 3GPP standardized in Release 5 the technology HSDPA (High Speed Downlink Packet Access). The HSDPA provides a cost effective solution to provide high-speed data to the customers specially focused to increase the overall cell capacity thanks to the fact that the resources are shared among the users. This project has consisted on the design of a HSDPA simulator and on the evaluation of the performance of VoIP and web browsing traffic in HSDPA. The idea of this project started on an industrial placement in Orange UK, in the department of Access Network. Between other tasks the CQI (Channel Quality Information) were modelled using samples taken from the live network. In order to do a more theoretical analysis and make use of the CQI modelling, after the placement, the design of the complete simulator has been made under the direction of Professor Ferran Casadevall. The objective of this project is then to simulate an HSDPA cell in different conditions, specially focused in different cell loading conditions such as: · Different number of users, up to 100 users per cell. · Different traffic profiles, choosing between VoIP and web users. Once the simulations have been carried out, the results have been analysed in detail, offering figures and facts of how the throughput and the traffic delay changes with different load conditions. As both the VoIP and web traffic have different thresholds of maximum delay defined by international entities, the simulations could be used to asses to define, the maximum number of HSPDA users in cell. This will help to capacity planners to decide the rollout strategy, based on the simulation results. This project has been developed with the tool Matlab. This tool has been chosen because it allows an effective code development and at the same time it is very useful to produce graphics and to compute difficult numerical calculations

EVEREST IST - 2002 - 00185 : D23 : final report

Deliverable públic del projecte europeu EVERESTThis deliverable constitutes the final report of the project IST-2002-001858 EVEREST. After its successful completion, the project presents this document that firstly summarizes the context, goal and the approach objective of the project. Then it presents a concise summary of the major goals and results, as well as highlights the most valuable lessons derived form the project work. A list of deliverables and publications is included in the annex.Postprint (published version

IST-2000-30148 I-METRA: D6.1 Implications in re-configurable systems beyond 3G (Part 1)

In this activity MIMO HSDPA is evaluated as the UMTS evolution that could allow a combination of high bit rate services, coverage and mobility with a good trade-off between cost and performance. This evaluation requires the definition of an objective framework for comparison between competing air interface technologies for Systems beyond 3G, and should be carried out in cooperation with other IST projects. The deliverable is complemented by analytically assessing channel capacity in flat Rician- and Rayleigh fading when ideal proportional fast scheduling, optimal rate adaptation, and various transmit diversity techniques are used.Preprin

Brzi paketni pristup

Data services and multimedia are expected to have significant growth over the next few years and will likely become the dominant source of 3G traffic. High Speed Downlink Packet Access (HSDPA) provides large enhancements over Wideband Code Division Multiple Access (WCDMA) for the downlink. HSDPA was standardized as part of Third Generation Partnership Project (3GPP) Release 5 and improved in later releases. The HSDPA peak date rate available in the terminals was initially 1.8 Mbps, but it has increased to 42 Mbps. HSDPA has been designed to increase downlink packet data throughput by means of fast physical layer retransmission and transmission combining as well fast link adaptation controlled by the Node B – i.e. a base transmission station (BTS). High Speed Uplink Packet Access (HSUPA) was part of 3GPP Release 6 with the first specification version in December 2004. The HSUPA peak data rate in the initial phase is expected to be 1–2 Mbps with later phase pushing the data rate to 11.5 Mbps. HSDPA and HSUPA together form High Speed Packet Access (HSPA).Očekuje se da će podatkovne usluge i multimedija imati značajan rast te će vjerojatno postati dominantan izvor 3G prometa u sljedećih nekoliko godina. Brzi paketski pristup u silaznom smjeru (HSDPA) pruža veliko unaprjeđenje u usporedbi sa na širokopojasnim višestrukim pristupom po kodnoj raspodjeli (WCDMA) za silazni smjer. HSDPA je normiran kao Release 5 od strane 3GPP te je unaprjeđivan u daljnjim izdanjima. U početku je raspoloživa brzina prijenosa podataka u korisničkim uređajima iznosila 1,8 Mbit/s, ali je sad povećana na 42 Mbit/s. HSDPA je osmišljen kako bi povećao brzinu prijenosa podataka u silaznom smjeru te pritom se koristi tehnikama brzog ponovnog slanja podataka na fizičkom sloju, brzom prilagodbom veze u baznoj postaji, itd. Brzi paketski pristup u uzlaznom smjeru pojavio se kao dio 3GPP Relase 6, a izišao je u prosincu 2004. U početnoj fazi HSUPA je omogućavala vršne brzine prijenosa podataka od 1 do 2 Mbit/s, dok trenutno omogućava brzine prijenosa podataka od 11,5 Mbit/s. Obje tehnologije, HSDPA i HSUPA zajedno, nazivaju se brzi paketski pristup (HSPA)

Optimization of Layer Selection with Unreliable RI in LTE Systems

This paper investigates the optimization of transmission spatial layer selection with unreliable rank indicator (RI) in downlink LTE systems. Taking the block error rate (BLER) into consideration, we propose an accurate throughput calculation (ATC) algorithm at user equipment (UE) side as well as at evolved NodeB (eNB) side. On the basis of ATC algorithm, we propose an accurate RI selection algorithm to periodically choose the preferred number of transmission spatial layers at UE side. Further based on acknowledgement (ACK)/ negative acknowledgement (NACK) history, channel quality indicator (CQI) is adjusted at eNB side to achieve the throughput optimal target BLER. By substituting the derived BLER into ATC algorithm, the optimal number of transmitted spatial layers in current downlink channel is derived at eNB side. Simulation results show that both the proposed CQI adjustment scheme for spatial layer selection and RI selection algorithm yield up significant throughput improvement for different evaluation scenarios in LTE systems